Defeating Dementia

New research and technology are providing tantalizing clues that quality sleep is vital to much more than simply refreshing the body. Dr. Carmen Westerberg, professor in TXST’s Department of Psychology and faculty fellow of the TXST Translational Health Research Center (THRC), has spent more than a decade exploring the links between sleep and cognitive function, including memory.  

“Until the 1990s, people just didn’t believe that there was anything special happening during sleep,” Westerberg says. “The conventional wisdom was that we’re resting. But our brain is actually more active when we’re asleep than when we’re awake.”  

Advances in medical technology, such as functional MRI brain scanning, have opened new avenues for studying brain function. Studies by Westerberg and others have shown that deep sleep, or “slow-wave” sleep, is particularly important for memory consolidation.  

“After you learn something new, that information isn’t just sitting dormant in your brain,” Westerberg says. “It undergoes a consolidation process that creates stable, enduring long-term memory. Our new knowledge is becoming integrated with existing knowledge.”  

The link with aging and dementia is that sleep tends to decline as people age. The average younger adult sleeps about seven to eight hours per night, versus about six hours a night for adults in their 60s and older.  

In one of Westerberg’s recent studies, volunteers—all over age 60—took an afternoon nap in a sleep lab. As they slept, electrical currents were passed through their brains via electrodes placed on the scalp. The group took memory tests before and after the experience.  

“In essence we were giving them a boost in slow-wave sleep, and we did show that their memory was better after,” Westerberg says.

It was an exciting and encouraging result, but Westerberg cautions that each study is just one step forward in understanding—not an easy cure for memory loss or cognitive decline. She’s watched the gradual progression of such research since her undergraduate studies in psychology.   

“I was always interested in memory,” she says. “I always had a pretty good memory, and I didn’t understand why other people didn’t. I wanted to know what was happening in the brain that allowed us to remember. After graduate school I did a postdoctoral fellowship at Northwestern University, and that’s where I got into learning how sleep is transforming our memories.”

Today, Westerberg is part of The Alliance of Researchers in Aging (ARIA), a collaborative group at Texas State formed in 2019 with a focus on interdisciplinary research in aging, including cognition, cognitive decline, dementia, and mental health.  

The connection between memory and sleep can vary from person to person, too. Westerberg’s most recent study, funded by the McKnight Foundation for Neuroscience Memory and Cognitive Disorders, looked at the sleep architecture of people with Highly Superior Autobiographical Memory (HSAM). People with HSAM aren’t necessarily better at learning or memorizing facts, but they have unusually precise recall for daily details of their lives—such as being able to remember what they had for breakfast or what was in the news on a specific day 20 years ago.  

Her study found that people with HSAM didn’t get more sleep or have a higher percentage of slow-wave sleep. What they did have were more “sleep spindles,” a very particular brain wave pattern that may be key to building lasting memories.  

“That’s very exciting because it suggests that part of what’s contributing to their superior memory is that they have more sleep spindles, and they are in better alignment with their slow waves,” Westerberg says. “But this was just a study about sleep. Next, we want to link these patterns to changes in their memory.”  

Collaborative groups like ARIA are important for helping researchers combine their findings and translate study results into practical treatments or wellness advice for aging populations, she notes.  

Next, Westerberg is launching a broader research study—in collaboration with TXST’s Translational Health Research Center—on how a variety of health and lifestyle factors affect aging and dementia.  

“ARIA is an essential partner for THRC, helping faculty and students explore healthy aging through research and career opportunities,” says Dr. Melinda Villagran, THRC executive director. “As a THRC Faculty Fellow, Dr. Westerberg’s expertise plays a critical role to help our center improve health across the lifespan through aging and dementia research conducted with ARIA members.”